Dark Rand. The real Forsaken have been so lame overall, that perhaps the most impressive Forsaken moment is Graendal escaping Rand. And all she did was escape. We don't have any truly awesome moments from them.

So I will say the awesomest Forsaken moments were in fact done by Dark Rand, whom I will classify as a Forsaken for that brief awesome period during TGS. Afterall, he channeled the TP and was basically doing the work of the Dark One. But for a brief moment we got to see what a real villain is like. Awesomely powerful, extremely intimidating, cruel, cunning, and ruthless.

Dark Rand channeling the TP to destroy Semi at the last moment was AWESOME. Dark Rand asking Cadsuane if she thought that the pattern would kill her if Dark Rand simply wished it to be so, followed by his promise that the next time he saw her face he would kill her was AWESOME. Dark Rand's plan and actions to kill Graendal(though failed) including using Amshalan and balefiring the entire complex and everybody in it were AWESOME. Dark Rand was by the far the best evil character the books have seen. He died too soon.

As miserable as ToM was, looking back I have to admit that TGS was pretty good for a book written by one other than RJ.

Lanfear would have had an AWESOME moment if she had shielded Egwene, Avi, and Rand and then killed Egwene and Avi right before Rand's eyes. Instead, depsite being in a fit of rage, she inexplicably manages to do no real harm to any of the main characters even though she lashes out at them while she is so beside herself that she had just skinned Karede alive and turned his skin into a balloon. Stuff like this pisses me off. Along those lines, another awful moment was Ishy sword fighting Rand in the sky (without a sword, no less). The only way Ishy could have been stupider was to challenge Rand to a sheep shearing contest, winner gets to kill the loser.

"I know that I am vastly more powerful than you in the OP, but I am going to risk my life by sword fighting you instead of just killing you or capturing you with the OP or TP in any of countless ways. I realize that you have been training with the sword and that I, by all accounts, am not particularly skilled in hand to hand combat. But dueling with you in the sky just seems like a good idea."

Semi murdering the imperial family (and presumably their Damane)in Seandar would have been an awesome moment if we had seen some of it on screen.

I don't dare get my hopes up that Demandred will have some AWESOME moments in AMOL.

I realize I raised the standard from "cool" in your post to "awesome" in mine. If the standard is "cool", then there are plenty of those moments, including the ones you mentioned.